Suggestions for replacing slow iMac componets?

Novice needs some help here!!

My late 2009 iMac is running Yosemite 10.10.3. Machine was running a little slow, but otherwise fine. Recently, it has been extremely slow, with the little spinning colored ball running for minutes at a time. Ran it in SAFE mode and rebooted - no improvement. Ran virus scan, which indicates no issues. Checked the resource usage screen, and indicated I still had 2GB memory available. I can't determine the EMC number, as there is no label posted on the iMac, but presuming EMC2309 based on processor. Machine runs so slow that I cannot download any of the software listed for system checks listed on the threads posted here . Processor is 3.03 GHz Intel Core 2 Duo. Memory is 4GB 1067 MHzDDR3. I believe hard drive is NVidia MCP79 AHCI SATA 1TB. I am willing to put some money into replacing components into an otherwise useful iMac. Already backed up data to backup hard drive, and created a boot disk on thumb drive.

Looking to replace hard drive with SSD, upgrade/add memory, and replace the processor if needed. Need some guidance on components and memory. If I can confirm the parts, I believe I can follow the install guides here.

1) What SSD hard drive should I replace the old drive with?

2) Should I replace all the DDRM with new, and is so, with what? Or simply add 4GB more of the same memory to the remaining two slots?

3) Should I replace the processor with new, and is so, with what? Can the processor be upgraded?

2 Answers

First you should make a good backup of your data on an external HD if you haven't already.

OK, here's the deal ... Overtime your system can get bogged down with overly large log and cache files. So I would start things here by running a app that can clean them out. Here's a good one you can get from the Apps Store: Disk Doctor. OK, the Next step is to free up space on your drive see if you can free up 1/4 to 1/3 of the drive free.

Next you likely need to check your HD for corruptions. The easiest thing here is to startup your system under an external drive or if you have a second Mac you can use OS-X Yosemite: Transfer files between two computers using target disk mode. In this case we are using the other Mac's Drive to boot up from so you can run Disk Utility to fix any errors both permissions & drive.

The next step is to defrag your drive. I like this app: Drive Genius. There are others, this one offers some other useful tools.

OK, so far we've addressed your HD your system should now be back with the same zip you saw it had day one. But you likely need more things done here. Given the systems age you likely have a forest of dust inside ;-} Time to open it up and using a soft paint brush and a can of can'ed air clean the dust out. You may want to install this App to monitor the systems fan & thermal sensors: TG Pro so you can track the improvement before and afterwards.

Today we have new drives that are much faster than what this system had installed. If you encountered any errors running Disk Utility on the drive its self or you want to get some more improvement here you could look at putting in a SSHD like Seagate's Desktop SSHD. Your system has a SATA II (3.0 Gb/s) port so what ever drive you get make sure it is able to work in a SATA II system. Many drives today are fixed SATA III (6.0 Gb/s) and won't reliably run in your system unlike this drive which has auto SATA speed sense. Given the systems age I would hold off putting in a SSD. While I love them they are costly for the larger units.

OK, the very last thing: RAM! The newer OS's do use more RAM just to run. So I do recommend upping the RAM here. You're in luck here with the latest firmware you can install up to 16 GB of RAM! I wouldn't go that high, maybe pushing it to 8 GB. In any case I would recommend checking the firmware level and make sure you're at least at the level listed for your system it also has some SATA port fixes as well.

Apple work like this, they say install new system on your old device it will be fast, but the truth is they want your mac slow for you think component are too slow and you go to the apple store spend all your money on the new 2000$ mac